The chemotherapeutic agent cisplatin and other platinum derivatives are front-line chemotherapeutic agents used in the treatment of solid tumors including ovarian, head and neck and testicular germ cell tumors. Cisplatin is a common cause of acute renal failure (ARF). Inflammation is thought to play a role in the pathophysiology of ARF. Caspase-1 deficient mice are protected against cisplatin-induced ARF (CIARF), as well as tubular cell apoptosis and necrosis. Caspase-1 inhibition is known to result in a decrease in the pro-inflammatory cytokines IL-13, IL-18, IL-1a and IL-6. However, inhibition of IL-13 or IL-18 is not protective against CIARF. Thus the grant proposal will focus on IL-1a and IL-6. Macrophages and natural killer (NK) cells are known sources and targets of IL-1a and IL-G. Macrophages and NK cells are activated by IL-1a and/or IL-6 to produce the cytolytic agents like perforin and granzyme (gzm) which may cause tubular injury. Thus, this proposal investigates the injurious role of macrophages and NK cells in CIARF. The overall hypothesis is that caspase-1-mediated production of IL- 1a and/or IL-6 in the proximal tubules (PT) of the kidney initiates a series of events that culminates in macrophage and NK cell infiltration into the kidney and subsequent ARF. Specific hypotheses that will be investigated: 1) The PT within the kidney is a source of IL-1a and/or IL-6. 2) IL-1a and/or IL-6 then activate macrophages which in turn produces IL-1a and/or IL-6 that activates NK cells. 3) Inhibition of IL-1a and/or IL-6 will attenuate macrophage and NK cell infiltration in ARF. Experiments will be carried out using an in vivo mouse model of CIARF. Time course experiments will be performed to describe IL-1a and IL-6 levels, as well as macrophage and NK cell infiltration relative to the onset of renal injury. Specific IL-1a and IL-6 inhibitions in addition to macrophage and NK depletions will be performed to elucidate their contributions to injury. The reciprocal relationships between these cytokines and inflammatory cells will also be determined. Electrochemiluminescence, immunofluorescent microscopy, and flow cytometry techniques will be utilized. RELEVANCE: Acute renal failure (ARF) continues to be a common illness, and is associated with high mortality, morbidity, and cost of health care. The mechanism of ARF is incompletely understood, but inflammation is thought to be play a major role. Better understanding of the underlying inflammatory mechanisms may lead to improved preventative and treatment strategies. [unreadable] [unreadable] [unreadable]